1. Field
The following description relates to a user interface, and more particularly, to a touch panel.
2. Description of the Related Art
A touch panel is one example of a kind of user input device used to determine whether a user generates an input and the position of the user's input by sensing the user's contact thereon. A user may input data or signals to a touch panel by contacting or pressing a surface of the touch panel with a finger, a stylus pen or the like. The touch panel may be used as a touch pad functioning as a substitute for a mouse in a laptop computer or a netbook, etc., or used in place of an input switch of an electronic device. Also, the touch panel may be used in association with a display. A touch panel which is mounted on the screen of a display device, such as a liquid crystal display (LCD), a plasma display panel (PDP), a cathode ray tube (CRT) and the like, is generally called a “touch screen”. A touch panel may be integrated with a display device to configure the screen of the display or may be attached additionally on the screen of the display.
In certain situations, a touch panel may be substituted for a user input device such as a keyboard, a trackball, or a mouse, and also may allow for simple manipulations. Moreover, the touch panel can provide users with various types of buttons according to the types of applications to be executed or stages of the executed application. Accordingly, a touch panel, and more specifically, a touch screen, has been used as an input device for electronic equipment, such as a mobile phone, a personal digital assistant (PDA), a portable multimedia player (PMP), a digital camera, a portable game, a Moving Picture Experts Group Layer-3 (MP3) player, etc., as well as an automated teller machine (ATM), an information trader, a ticket vending machine, etc.
A touch panel can be classified into a resistive type, a capacitive type, a saw type, an infrared type, etc., according to methods of sensing user's inputs. A capacitive type touch panel determines whether a user generates an input and the position of the user's input by measuring variations in capacitance due to contact or pressure. However, the capacitive type touch panel fails to offer users a sense of input, that is, a feeling of recognition that a user gets upon inputting. In order to overcome this disadvantage, a method of installing a vibration motor under a touch panel has been proposed. The method offers users a sense of input by vibrating the whole touch panel using the vibration motor when a user's contact is sensed. Recently, a method of offering various senses of inputs by adjusting the magnitude or frequency of vibration has been developed.